Methods and apparatus for steering an ATV
Methods and apparatus related to the suspension and steering of all terrain vehicles (ATVs) are disclosed. An ATV having a frame and a wheel carrier for rotatably supporting a wheel is provided. A tie rod is coupled to the wheel carrier at an outer joint. An inner joint of the tie rod is preferably located in a desirable location. A method for identifying the desirable location may include the steps of defining a first reference plane associated with a full compression position of the suspension, defining a second reference plane associated with a full extension position of the suspension, identifying a reference line formed by an intersection of the first reference plane and the second reference plane, and selecting a location proximate the reference line as the desirable location for the inner joint.
Latest Polaris Industries Inc. Patents:
This application is a continuation of U.S. application Ser. No. 10/099,202, filed Mar. 13, 2002, now U.S. Pat. No. 6,767,022, which claims the benefit of U.S. Provisional Application No. 60/313,599, filed Aug. 20, 2001 and U.S. Provisional Application No. 60/313,417, filed Aug. 17, 2001. The entire disclosure of the fore mentioned applications is hereby incorporated by reference.
FIELD OF THE INVENTIONThe present invention relates generally to all terrain vehicles having a straddle-seat for accommodating a rider and a set of handle bars for receiving the hands of the rider. More particularly, the present invention relates to suspension and steering systems for all terrain vehicles.
BACKGROUND OF THE INVENTIONIn recent years, all terrain vehicles (ATVs) have gained widespread popularity. ATVs are commonly used in hunting, trail riding and utility applications such as the wide variety of maintenance activities which take place on a farm. Attachments are available for ATVs for use in utility applications such as plowing snow, mowing grass and hauling materials.
Perhaps the most common ATV application is trail riding. Trail riding on an ATV allows an ATV enthusiast to travel through areas which are not accessible by ordinary automobiles. Modern ATVs, can cover ground very rapidly and can cover great distances. Frequently, ATV enthusiasts ride their ATV for many hours straight and cover many miles. If the rider is subjected to excessive jarring while traveling over rough terrain, operator fatigue may result particularly during a long ride. During such long rides, an ATV may be used to carry a rider through a wide variety of terrain. Terrain which may be encountered includes forests, swamps, and deserts. Frequently ATVs are called upon to travel across rugged terrain at relatively high speeds.
Part of the thrill of riding an ATV is encountering challenging terrain, and through the performance of the ATV and the skill of the rider passing through the terrain. The ability to tackle challenging terrain may depend on the performance of the steering systems, suspension, and the interface between the rider and the ATV. These elements each effect the riding experience enjoyed by the ATV enthusiast.
SUMMARY OF THE INVENTIONThe present invention relates generally to all terrain vehicles having a straddle-seat for accommodating a rider and a set of handle bars for receiving the hands of the rider. More particularly, the present invention relates to suspension and steering systems for all terrain vehicles. An ATV in accordance with the present invention may include a frame and a wheel carrier for rotatably supporting a wheel.
In certain implementations, the present invention comprises a steering system including a steering column. A steering arm is fixed to the steering column proximate a proximal end thereof. In certain implementations, a pair of handle bars are fixed to the steering column proximate a distal end thereof. In one aspect of the present invention, the proximal end of the steering column is rotatably supported by a mounting bracket. In certain implementations, the mounting bracket also rotatably supports a left intermediate arm and a right intermediate arm. The left intermediate arm may be advantageously coupled to the steering arm by a left link, and the right intermediate arm may be coupled to steering arm by a right link.
The steering system may also include a left tie rod and a right tie rod. Each tie rod may be pivotally coupled to a protrusion of a wheel carrier at an outer joint of the tie rod. Each tie rod may also be pivotably coupled to an intermediate arm at an inner joint of the tie rod. The steering system may be used to rotate a wheel carrier about a steering axis of the wheel carrier. In a preferred embodiment, a suspension and steering system is provided which is dimensioned so that movement of the suspension through its travel between a full extension position and a full compression position is unlikely to cause rotation of the wheel carrier about the steering axis. In an advantageous implementation, the inner joint of each tie rod is located so that rotation of the wheel carrier about the steering axis due to deflection of the suspension will be minimized.
Methods in accordance with the present invention may be used to locate a desirable position for the inner joint of each tie rod. A method for identifying the desirable location may include the steps of defining a first reference plane associated with a full compression position of the suspension, defining a second reference plane associated with a full extension position of the suspension, and identifying a reference line formed by an intersection of the first reference plane and the second reference plane.
A position may be selected proximate the reference line as the desirable position for the inner joint. In certain implementations, the inner joint is located so that the reference line intersects the inner joint. In some cases, the inner joint may be advantageously located so that the reference line intersects a center of the inner joint. In other cases, the inner tie rod joint may be located so that the center of the inner joint is disposed within a reference cylinder centered on the reference line.
In certain implementations, the step of defining the first reference plane comprises the steps of locating an instant center axis of the suspension when the suspension is at full compression and locating of a central point of the outer joint of the tie rod when the suspension is at full compression. In these implementations, the first reference plane is defined by the instant center axis and the central point located for the suspension at full compression.
In certain implementations, the step of defining the second reference plane comprises the steps of locating an instant center axis of the suspension when the suspension is at full extension and locating of a central point of the outer joint of the tie rod when the suspension is at full extension. In these implementations, the second reference plane is defined by the instant center axis and the central point located for the suspension at full extension.
The following detailed description should be read with reference to the drawings, in which like elements in different drawings are numbered identically. The drawings, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the invention. Examples of constructions, materials, dimensions, and manufacturing processes are provided for selected elements. All other elements employ that which is known to those of skill in the field of the invention. Those skilled in the art will recognize that many of the examples provided have suitable alternatives that can be utilized.
Suspension 128 also includes a wheel carrier 134 that is coupled to upper arm 130 and lower arm 132. In the exemplary embodiment of
In the embodiment of
Assembly 126 also comprises a steering system 148 that is configured to rotate wheel carrier 134 about steering axis 182. Steering system 148 includes a steering column 150 and a left tie rod 152A. An outer end of left tie rod 152A is pivotally coupled to a protrusion 154 of wheel carrier 134. Steering column 150 is preferably rotatably supported by frame 120. A pair of handle bars may be fixed to steering column 150 proximate a distal end thereof.
Suspension 128 also includes a spring assembly 142 having a first end rotatably coupled to frame 120 and a second end rotatably coupled to lower arm 132. In the embodiment of
In the embodiment of
Steering system 248 also includes a left tie rod 252A and a right tie rod 252B. Left tie rod 252A includes an inner joint 264A and an outer joint 266A. In
Right tie rod 252B includes an inner joint 264B and an outer joint 266B. In
Steering system 248 may be used to rotate wheel carrier 234 about a steering axis 282. In the embodiment of
An exemplary method for identifying a desired position for the inner joint 264A and inner joint 264B may include the following steps.
-
- 1. Identify the instant center axis when the suspension system is at full compression.
- 2. Identify the instant center axis when the suspension system is at full extension.
- 3. Identify a first plane defined by the center of the outer tie rod ball and the instant center axis at full compression.
- 4. Identify a second plane defined by the center of the tie rod ball and the instant center axis at full extension.
- 5. Identify a reference line formed by an intersection of the first plane and the second plane.
- 6. Identify a reference cylinder disposed about the reference line.
- 7. Select a desired position disposed within the reference cylinder.
Suspension 328 also includes a wheel carrier 334 that is coupled to upper arm 330 and lower arm 332. In the exemplary embodiment of
Suspension 328 also includes a tie rod 352 having an inner joint 364 and an outer joint 366. In
Suspension 328 may assume various positions. For example, suspension 328 may have a fully extended position and a fully compressed position. In
It is to be appreciated that methods an apparatus in accordance with the present invention may be used with various types of suspension systems without deviating from the spirit and scope of the present invention. Examples of suspension systems that may be suitable in some applications include double A-arm suspensions, McPherson strut suspensions, and trailing arm suspensions.
Protrusion 554A and protrusion 554B form part of a steering system 548. Steering system 548 includes a steering arm 556. In the embodiment of
Steering system 548 also includes a left tie rod 552A and a right tie rod 552B. Left tie rod 552A includes an inner joint 564A and an outer joint 566A. Left tie rod 552A is coupled to protrusion 554A at outer joint 566A. A left reference line LRL is illustrated in
In
In
The second reference plane may be defined by locating an instant center axis of suspension 728 when suspension 728 is at full extension and locating central point 786 of the outer joint 766 of the tie rod 752 when suspension 728 is at full extension. Thus, the instant center axis and the central point of the outer joint define the second reference plane when suspension 728 is at full extension.
Numerous characteristics and advantages of the invention covered by this document have been set forth in the foregoing description. For example, some embodiments of the present invention provide a suspension and steering system for an ATV that is dimensioned so that movement of the suspension through its travel between a full extension position and a full compression position is unlikely to cause rotation of the wheel carrier about a steering axis. It will be understood, however, that this disclosure is, in many respects, only illustrative. Changes may be made in details, particularly in matters of shape, size and ordering of steps without exceeding the scope of the invention. The invention's scope is, of course, defined in the language in which the appended claims are expressed.
Claims
1. A method comprising the steps of:
- providing a vehicle frame and a wheel carrier coupled to the vehicle frame by a suspension;
- coupling a tie rod to the wheel carrier at an outer tie rod joint;
- positioning an inner tie rod joint of the tie rod proximate a reference line defined by the intersection of a first reference plane and a second reference plane;
- wherein the first reference plane is defined by a center of the outer tie rod joint and a first instant center axis of the suspension while the suspension is in a full compression position; and
- wherein the second reference plane is defined by the center of the outer tie rod joint and a second instant center axis of the suspension while the suspension is in a full extension position.
2. The method of claim 1, wherein the inner tie rod joint is positioned so that the reference line intersects the inner tie rod joint.
3. The method of claim 2, wherein the inner tie rod joint is positioned so that the reference line intersects a center of the inner tie rod joint.
4. The method of claim 1, wherein the inner tie rod joint is positioned so that a center of the inner tie rod joint is disposed within a reference cylinder centered on the reference line.
5. The method of claim 4, wherein the reference cylinder has a radius of less than about 3.0 centimeters.
6. The method of claim 5, wherein the reference cylinder has a radius of less than about 2.0 centimeters.
7. The method of claim 6, wherein the reference cylinder has a radius of less than about 1.0 centimeter.
8. The method of claim 1, wherein the inner tie rod joint is positioned so that a center of the inner tie rod joint is disposed proximate an intersection of the reference line and a second reference line.
9. The method of claim 8, wherein the second reference line is perpendicular to a longitudinal axis of the vehicle frame.
10. The method of claim 1, wherein the suspension comprises a McPherson strut suspension.
11. The method of claim 1, wherein the suspension comprises a double A-arm suspension.
12. The method of claim 1, further including the step of coupling an intermediate arm to the tie rod at the inner tie rod joint.
3827516 | August 1974 | Lucia |
3884314 | May 1975 | Schneider et al. |
3912030 | October 1975 | Payne |
3942816 | March 9, 1976 | Scherenberg et al. |
4448441 | May 15, 1984 | Brummer et al. |
4610461 | September 9, 1986 | Guzzetta |
4620715 | November 4, 1986 | Takahashi |
4625982 | December 2, 1986 | Matsuo |
4650029 | March 17, 1987 | Foote et al. |
4657271 | April 14, 1987 | Salmon |
4671521 | June 9, 1987 | Talbot et al. |
4699234 | October 13, 1987 | Shinozaki et al. |
4749205 | June 7, 1988 | Takahashi et al. |
4822073 | April 18, 1989 | Tanahashi et al. |
5000476 | March 19, 1991 | Lindorfer et al. |
5029664 | July 9, 1991 | Zulawski |
6009966 | January 4, 2000 | Olson et al. |
6125958 | October 3, 2000 | Olson et al. |
6311798 | November 6, 2001 | Anderson |
6343666 | February 5, 2002 | Olson et al. |
6357543 | March 19, 2002 | Karpik |
20020017765 | February 14, 2002 | Mallette et al. |
JP 62218209 | September 1987 | JP |
Type: Grant
Filed: Jul 19, 2004
Date of Patent: Feb 21, 2006
Assignee: Polaris Industries Inc. (Medina, MN)
Inventor: Mark Chevalier (Forest Lake, MN)
Primary Examiner: Eric Culbreth
Attorney: Fredrikson & Byron
Application Number: 10/894,097
International Classification: B62D 7/06 (20060101);